Open source

Someone recently asked me a question: How can I save time and script size by specifying a range of IP addresses or ports using iptables? In old version of iptables IP address ranges are only valid in the nat table (see below for example). However newer version does support option that allows you to specify …

I got a chance to play with Squid and iptables. My job was simple : Setup Squid proxy as a transparent server. Main benefit of setting transparent proxy is you do not have to setup up individual browsers to work with proxies. System: HP dual Xeon CPU system with 8 GB RAM (good for squid). Eth0: IP:192.168.1.1 Eth1: IP: 192.168.2.1 (192.168.2.0/24 network (around 150 windows XP systems)) OS: Red Hat Enterprise Linux 4.0 (Following instruction should work with Debian and all other Linux distros) Eth0 connected to internet and eth1 connected to local lan i.e. system act as router. Server Configuration Step #1 : Squid configuration so that it will act as a transparent proxy Step #2 : Iptables configuration Configure system as router Forward all http requests to 3128 (DNAT) Step #3: Run scripts and start squid service First, Squid server installed (use up2date squid) and configured by adding …

Normally Linux systems can only read from Windows NTFS partitions, but not write to them which can be very annoying if you have to work with Linux and Windows systems. This is where ntfs-3g comes into play. ntfs-3g is an open source, freely available NTFS driver for Linux with read and write support. This tutorial shows how to use ntfs-3g on a Fedora 7 desktop to read from and write to Windows NTFS drives and partitions. This document comes without warranty of any kind! I want to say that this is not the only way of setting up such a system. There are many ways of achieving this goal but this is the way I take. I do not issue any guarantee that this will work for you! Preliminary Note I have tried this on a Fedora 7 desktop with an external NTFS USB hard drive. Using ntfs-3g Fortunately, Fedora …

This tutorial will guide you through installation and configuration of Lintrack, a GNU/Linux distribution specialized in networking tasks. We will give two LANs access to the internet along with DHCP and DNS cache servers, and then we will connect our networks using OpenVPN in bridging mode. You should be running all these in well under an hour, thanks to the unified configuration interface of Lintrack. The Plan The diagram below presents the network we are about to create. Hosts rt1 and rt2 are our routers running Lintrack. Both of them have Internet connection (e.g. via DSL modems), a public IP address available on eth0 interface and a Local Area Network behind. You will need two x86 hosts (a typical PC should be good enough), with at least 128MB of RAM and 256MB of storage space (can be a Compact Flash card), some Fast/Gigabit Ethernet cards and, if you wish, WiFi …

The Linux Foundation yesterday announced that Nokia Siemens Networks has become a member. Nokia Siemens Networks will work with the foundation and its members to continue improving Carrier Grade Linux (CGL). Nokia Siemens Networks, a leading enabler of communications services, will be working with the foundation specifically on Linux-based technologies for use in User Plane and Control Plane Network Elements, as well as embedded applications. This is expected to lead to further integration of CGL specifications with the Linux Standard Base (LSB) to deliver a standard that works for these expanding Linux markets. “Linux has become a very natural fit for telecom network and device manufacturers who are looking for an operating system from which they can easily and cost-effectively build differentiated services and value,” said Jim Zemlin, executive director of The Linux Foundation. “There is no question that the massive success of Linux in telecom is key in today’s …

To mark the second birthday of the openSUSE project, the community program last week celebrated with two announcements – the availability of the first beta of openSUSE 10.3 and the growth of the openSUSE Build Service with a new end-user interface. The openSUSE Build Service is a framework that provides an infrastructure for software developers to create and compile packages for multiple Linux distributions. It addresses the problem that developers have in providing their software across multiple Linux platforms. The development team released the first version of the build service’s end-user interface, with which users of any openSUSE, SUSE Linux Enterprise, Fedora, Debian, Ubuntu or Mandriva distribution can search and browse new software for their distribution. In the past four months, more than 13 million packages have been downloaded from the openSUSE Build Service. Currently there are more than 700 projects and 20 000 software packages available.

Lenovo will offer a version of Linux on its ThinkPad notebooks beginning in the fourth quarter, the company announced Monday. The Chinese PC maker has selected Suse Linux Enterprise Desktop 10 from Novell as its first supported entry into the world of open source. Though ThinkPads have been certified to run Linux in the past, this is the first time Lenovo will support the hardware and operating system directly. Novell will be responsible for providing operating system updates to Lenovo’s customers. ThinkPads with Suse Linux will be available to Lenovo’s commercial customers and individuals. The announcement coincides with the opening of the LinuxWorld conference in San Francisco on Monday. Lenovo is not the only top PC manufacturer to offer a version of the open-source operating system preinstalled on its PCs. In May, Dell opted for the Ubuntu version of Linux on a smattering of notebooks and PCs. Dell should also …

This year’s Black Hat was pretty much summed up in a prescient keynote by Richard Clarke, the nation’s former cyber security czar now novelist and chairman of Good Harbor Consulting. Clarke said “we’re building more and more of our economy on cyberspace 1.0, yet we have secured very little of cyberspace 1.0.” The apparent speed gained in Ajax (Asynchronous JavaScript and XML), which is technology that divides processing tasks between the Web server (Web site) and the Web client (browser), has opened Web 2.0 to some old school attacks. Nothing more clearly demonstrated this than a live hijack of a gMail account. In a talk originally to have been presented alongside his colleague David Maynor, Errata Security CEO Robert Graham demonstrated for a standing room only crowd how he was able to use a tool called Hamster and Ferret to sniff the wireless airwaves for the URLs of Web 2.0 …

The are a couple of things that are essential to any hacker’s walk of life. To name a few, there’s the ubiquitous flash drive for data transfer. You have the crossover cable for even faster data transfer. There’s the WiFi antenna for high gain and strong amplification.   Possibly, you might find a video capture card in the computer. Of course, there’s the ubiquitous laptop and desktop computer. But what software is on these computers? Undoubtedly, you will find at least two operating systems, most often Windows and Linux. But with Linux, there are several different distributions. Is there a specific one? With hackers and crackers, there is only one Linux distro out there. It is called Backtrack.